package com.eagift.nettyDemo;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpHeaderNames;
import io.netty.handler.codec.http.HttpHeaderValues;
import io.netty.handler.codec.http.HttpObject;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.util.CharsetUtil;

/**
 * @Description:创建自定义助手类
 * @author elinkme
 *
 */
//SimpleChannelInboundHandler,对于请求来讲,其实相当于[入站,入境]
public class CustomHandler extends SimpleChannelInboundHandler<HttpObject> {

    @Override
    public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...注册");
        super.channelRegistered(ctx);
    }

    @Override
    public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...移除");
        super.channelUnregistered(ctx);
    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...活跃");
        super.channelActive(ctx);
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...不活跃");
        super.channelInactive(ctx);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...读取完毕");
        super.channelReadComplete(ctx);
    }
    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        System.out.println("用户事件触发...");
        super.userEventTriggered(ctx, evt);
    }

    @Override
    public void channelWritabilityChanged(ChannelHandlerContext ctx) throws Exception {
        System.out.println("channel...可写更改");
        super.channelWritabilityChanged(ctx);
    }



    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        System.out.println("channel...捕获到异常");
        super.exceptionCaught(ctx, cause);
    }

    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        System.out.println("助手类添加");
        super.handlerAdded(ctx);
    }

    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
        System.out.println("助手类移除");
        super.handlerRemoved(ctx);
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
        // 获取channel
        Channel channel = ctx.channel();
        if (msg instanceof HttpRequest) {
            // 显示客户端的远程地址
            System.out.println(channel.remoteAddress());
            // 定义发送的消息
            ByteBuf content = Unpooled.copiedBuffer("{\"message\":\"Hello netty\"}", CharsetUtil.UTF_8);
            // 构建一个http response
            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK,
                                                                    content);
            // 为响应增加数据类型和长度
            response.headers().set(HttpHeaderNames.CONTENT_TYPE, HttpHeaderValues.APPLICATION_JSON);
            response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());
            // 把响应刷到客户端
            ctx.writeAndFlush(response);

        }
    }

}
